The variety of birdhouses and similar animal shelters that exist is indicative of the number of people whose love of animals takes the form of providing various shelters and food for nature's creatures. Birdhouses are among the most popular and common forms of such shelters.
Such structures provide shelter for a variety of creatures. For example, birdhouses are designed for a variety of different birds, determined, in part, by the size and shape of the houses themselves, and by the sizes of the access openings or entrance holes into the houses.
Unfortunately, birds and the nests, even when in these houses, are often subject to attack by other larger, preying animals, such as, for example, squirrels or even larger birds. While such animals may not be able to enter the entrance holes of birdhouses designed for smaller birds, they often have the ability to rech their heads, paws, or claws into the house and damage the nest and/or the eggs, or harm baby birds within the house.
Birdhouse access openings or entrance holes must be of a certain size in order to permit access to the birds for which they are designed. The diameters of entrance holes typically range in size between about one inche and about wto and one-half inches. While many entrance holes are relatively small, they are large enough to permit some access to attacking or other unwanted creatures.
It would be desirable, therefore, to be able to protect the birds inside the house, particularly baby birds during the days immediately after birth when they are at peril and risk, while simultaneously providing for convenient and ready access to the birds for which the houses are designed.